Cylindrical shaped vinyl or polyvinyl fenders or fenders are commonly provided around the sides of a boat for absorbing the impact between the boat and the dock during docking. The fenders are hung by ropes tied to cleats mounted on the gunwale or deck of the boat. As the water level relative to a dock changes due to tide or due to different dock structures to which the boat may have to dock, it has been problematic to boaters of having to vary the vertical position of the fenders from time to time to compensate for such variations. Such task is difficult to carry out on the boat since one must climb onto the small footholds of the gunwale or the front deck to raise and adjust each bumper individually. Some boats are provided with only a narrow walkway around the gunwale; furthermore, the boat is usually in motion riding up and down on waves and the footholds and the deck may also be wet and slippery. This creates a potentially dangerous situation for the person climbing or walking around the gunwale or the deck of the boat to adjust the fenders and may fall or be thrown overboard in the process. It is even more dangerous to carry out in the rain or in a storm.